Shaped charge



Oct. 21, 1958 J. H. CHURCH ET AL 2,356,850

I SHAPED CHARGE Filed March 22. 1954 INVENTOR-S J1: seph H- BhyrczhEraora J- Kessenic h United States Patent SHAPED CHARGE Joseph Church,Austin, Minn., and Gregory J. Kessenich, Madison, Wis., assignors to theUnited States of America as represented by the Secretary of the ArmyApplication March 22, 1954, Serial No. 417,981

5 Claims. (Cl. 102----24) (Granted under Title 35, U. S. Code (1952),see. 266) The invention described in the'specification and claims may bemanufactured and used by or for the Government for governmental purposeswithout the payment to us of any royalty thereon.

This. invention relating to shaped charges, is a continuation-in-part ofour application Serial No. 158,047 filed April 25, 1950, now abandoned.

The principal object of our invention is to provide a shaped charge witha cavity form which will enhance the directive effect of the cavity uponthe forces of detonation which are focused therethrough than heretoforeknown in the art.

Other and important objects will be apparent to those skilled in thisart from the following description when considered with theappended-drawing in which:

The. single view discloses a vertical sectional view through a shapedcharge provided with one form of cavity in accordance with ourinvention.

We have for convenience chosen to illustrate our present invention inconnection with a shaped charge generally indicated at which is confinedwithin and fits a casing externally configured about a centrallongitudinal axis of symmetry 11 so as to provide a lower truncatedconical section 12 and integral upwardly projecting cylindrical section13.

As shown, the charge 10 is shaped to define a conical surface 15symmetrical of axis 11 and having its base circumference or circlecoincident with the smaller circumference of a frusto-conical section 12also symmetrical of axis 11. This frusto-conical surface may beconsidered to haveformed in its surface adjacent its largercircumference, first and second annular channels each shown as V-shapedin cross section. Thus the cross section of the first channel is definedby a first pair of sides 15a and 15b and the cross section of the secondchannel is defined by sides 15c and 15d both having an apex anglesubstantially equal to the apex angle of frustoconical surface 15. Thebisectors 17 of the angles formed between the respective pairs of sides,intersects axis 11 at points forwardly of the open face of the shapedcharge. As shown the surfaces generated by sides 15a and 150 areparallel as are those generated by sides 15b and 15d. It is thus seenthat the entire shaped cavity is a generally rearwardly convergentsurface of revolution coaxial and symmetrical about axis 11, with thesurfaces 15d, 15c and 15a, 15b paired to form secondary shaped cavities16 symmetrical about minor axes 17 and with the force of explosiondirected inwardly in a manner to cause the effect of the secondarycavities 16 to augment the blast efiect produced by the primary cavity14.

The charge 10 as shown may bedetonated through boosters 18, 19 bydetonator 20 in difierentially timed relation so as to cause thedetonation waves from sections 12 and 13 of the charge 10 to reach thecavities 14, 16 substantially simultaneously or in preselected order. Asshown in the drawings the annular booster 19 is substantially U-shapedin cross section and is embedded in-the charge 10 adjacent the forwardend thereof so thatits legs are directed inwardly of the charge and inaxial alignment with the axes 17-17 for the purpose of producingdetonation waves in alinement with each of the apices of secondarycavities 16.

As indicated the detonator 20 is provided with a component detonator 21adapted to detonate the annular booster 19 throughout its lengthsimultaneously and with a depending booster component 22 adapted todetonate the booster 18. Action of detonator 20 is initiated by theinitiator 23 and the time sequence of detonating the detonableexplosives 24 in detonator components 21, 22 by the ratio of fuse powder25 to detonable explosive in each of the detonator components.

As we have merely shown charge 10 as having the :external figurationdisclosed for purposes of illustration we do not intend thereby to belimited to such external configuration but contemplate configurations ofany appropriate geometric form.

Likewise we have shown primary cavity 14 of generally rearwardlyconverging conical form merely for purposes of illustration andcontemplate secondary cavities 16 as being of any appropriate symmetriccross sectional form arranged in any appropriate symmetrical dispositionabout axis 11 to accomplish our stated principal object. As thesymmetric forms appropriate for use in shaping cavities 14, 16 are sonumerous and well known in the art of shaped charges we do notconsiderit .necessary to specifically enumerate and/or disclose them inthe drawings to make it clear to those skilled in the art that all suchshapes may be utilized in cavities 14, 16.

The cavities 14, 16 may be lined with complemental liners 26, 27 made ofany metallic or non-metallic material appropriate for such use. Theliners 26, 27 may be made integrally or as components either secured orunattached to each other and will be made of such thickness as is calledfor by the purpose to be served. In interpreting the claims, the forwarddirection is from top to bottom, along axis 11, as the parts are viewedupon the figure of the drawing.

We claim:

1. In a demolition unit, a frusto-conical portion of sheet materialunited at its end of smaller diameter with a tubular neck portion ofequal diameter, to form a casing, said portions having a common axis ofsymmetry, a solid charge of explosive fitting said casing, the face ofsaid charge opening through the larger end of said frusto-conicalportion and having a cavity therein symmetrical about said axis anddefined by a forwardlyopening conical surface of first apex anglemerging at its base into a frusto-conical surface of second apex anglegreater than said first angle, both said surfaces being symmetricalabout said common axis, a first booster in detonating relation with theexplosive in the rearward end of said neck portion, a second annularbooster extending about said frusto-conical portion in detonatingrelation with the explosive charge therein and coaxial of said axis, asingle detonator operatively associated with both said boosters andsymmetrical of said axis rearwardly of said first booster, saiddetonator including shaped charges adapted for simultaneously directingflame onto both said boosters to initiate the same.

2. The demolition unit of claim 1, said detonator including concentricfirst and second radially spaced hemispherical elements of lesser andgreater radii respectively, and symmetrical about said axis to define ahemispherical shell between them and a tubular element fixed with saidfirst hemispherical surface and extending radially thereof forwardlyalong said common axis to a point adjacent said first booster, a unitaryexplosive priming charge filling said shell and tubular element andPatented Oct. 21, 1958 shaped to direct an initiating flame onto saidfirst and second boosters, respectively. I

3. In a demolition unit, a frusto-conical portion of sheet materialunitedat .its end of smaller diameter with I I5 having afrusto-conicalportion integral at the end of I I smallest diameter witha cylindrical neck portion, a

a tubular neck portion of equal diameter, said portions having a -commonaxis ofsymmetry and jointly forminga-casing, a solid charge of explosivefitting within said casing, the face of said charge opening throughthe'I larger end .of said xfrusto-conical portion and having a cavitytherein symmetrical about said axis anddefin'ed by a forwardly-openingconical surface of first apex angle I having its basecircumferencecoincident with the smaller circumference of afrusto-conical-surface having a larger apex angle than said conicalsurface, said frusto-conical surface having first and second channels ofuniform cross section in planesradial of said .axis, a firstboo'ster Ifixed in detonating relationwith said'explosive charge at the rearward.end of said tubular portion, a second annular booster fixed indetonating relation with said charge I adjacent the bottoms ofsaidchannels, asingle detonator operatively associated with both saidboosters positioned symmetricallyof said common. axis .and initiable' toI simultaneously project flame into both said boosters toi initiate thesame. I I I I I '4; The demolition unit. of claim 3, said detonatorineluding concentric first and second radiallyp'spaced hemispherical,elements of lesser and greater radii, re-

its exposed surfaces shaped to direct :flame onto said first and secondboosters, respectively, and means carpriming charge. I I 5. .In a shapedcharge demolition unit, a main charge cav-ity. in said. frusto-conicalportion at the end of largest diameter, saidsca'vity' and cylidricalportion being I symmetrical about the longitudinal axis of said frusto-=conicalportion, a first booster charge overlying the rear- I Ward end ofsaid neck. portion, a second annular boosteroverlying a portion of saidfrusto-conical charge adja- I I cent said cavity, a single detonatoroperatively associatedwith both said boosters and symmetrical about saidaxis 15 rearwardlyof said first booster, said detonatorinclud-' I ing.shaped. charges adapted and arranged to direct a .jet of flame onto saidfirst booster and an annular jet of flame onto said second booster. I Il i i I 1 References Cited in the file' of'this patent. UNITED STATESPATENTS I I FOREIGN PATENTS 1,043,041 I OTHER-REFERENCES Sukharevsky:Techuica i Snabschenie, vol. 170; pages" I I I l3-.-1.8 (1925). Libraryof Congress, call'No. U4.V884,

wesen May 1914, page 184.

3. No: 6, pages 563482 (1948); I

- Ze-itschrift fur das .Gesam'te Schie ssun d Sprengstofi Birkhofi et.al.: Journal of Applied Physics, vol. 19,

